In the foundry industry, rotary cylinders are used on various pieces of equipment such as kilns, mixers, dryers, coolers, screens, mills, furnaces, blenders, and calciners. All of these pieces of equipment rotate on either two or more forged steel races which are called riding rings. Riding rings are steel forgings usually machined in one piece and shop mounted in one piece when the rotary unit is fabricated. After an extensive time in use, these rings develop surface cracks and must be replaced. Replacement of damaged or worn rings is very time consuming and expensive because of the size of the rotary cylinders, sometimes ten to twelve feet in diameter and two hundred fifty feet long. Many parts must be disassembled before the ring may be removed from the end of the drum. Rotary cylinders vary in size from small 2'-3' diameter units, to 10'-12' diameters.times.250' long limestone or cement kilns which could require five or six rings. Depending on the particular situation, the repair could cost from thousands to hundreds of thousands of dollars in labor and loss of production.
The split riding ring design eliminates the need to remove associated equipment, feeding or removing product from the rotary drum such as conveyors, feeders, breechings, dust hoods, ducts, etc. The split ring design has not been available until this time because when the one piece ring was split and reattached, the reattachment methods used have not been reliable and have caused maintenance problems. The split riding ring as disclosed has resolved these problems and has performed as well as a one piece unit. The shear stress under tension with the splice used in this invention is some ten times stronger than the forging itself.